Prime Minister John Key will reveal more details of the Government's asset sales programme tomorrow against the likely backdrop of sizeable protests.

Key confirmed his closing speech to the National Party conference in Auckland this weekend would be focused on the economy and would "firm up" some of the details around the Government's plan to sell a minority stake in the four State-owned power companies and more of Air New Zealand.

He would not go into further detail but the speech is likely to confirm sweeteners designed to keep the shares in New Zealand hands.

Around 100 students and activists matched on the Sky City conference to protest against National's education policies.

The demonstrators carried a coffin to mourn the 'death' of education.

They were held back by a heavy police presence. Earlier a handful of people greeted delegates with an anti mining demonstration.

A Stop the War on the the Poor protest is expected tomorrow.

More protests are expected outside the conference at Sky City tomorrow coinciding with Mr Key's speech and he used today's conference opening to warn them that the Government would not back down.

Key said anyone was free to protest in New Zealand "and that's what makes New Zealand great", but National had campaigned in 2011 on a "very clear plan" for New Zealand and had won "an absolute authority and mandate" to implement it.

Earlier today, Key acknowledged the "terrible shooting tragedy" in the United States and said it was an "unspeakable horror".

"Our thoughts go out to those who have lost loved ones as a result of that terrible tragedy," he said.